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Jack Steiner9a0deec2008-07-29 22:33:58 -07001/*
2 * SN Platform GRU Driver
3 *
4 * DRIVER TABLE MANAGER + GRU CONTEXT LOAD/UNLOAD
5 *
Jack Steiner8820f272009-06-17 16:28:36 -07006 * Copyright (c) 2008 Silicon Graphics, Inc. All Rights Reserved.
Jack Steiner9a0deec2008-07-29 22:33:58 -07007 *
Jack Steiner8820f272009-06-17 16:28:36 -07008 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
Jack Steiner9a0deec2008-07-29 22:33:58 -070021 */
22
23#include <linux/kernel.h>
24#include <linux/slab.h>
25#include <linux/mm.h>
26#include <linux/spinlock.h>
27#include <linux/sched.h>
28#include <linux/device.h>
29#include <linux/list.h>
Jack Steiner7f2251b2009-12-15 16:48:08 -080030#include <linux/err.h>
Linus Torvalds268bb0c2011-05-20 12:50:29 -070031#include <linux/prefetch.h>
Jack Steiner9a0deec2008-07-29 22:33:58 -070032#include <asm/uv/uv_hub.h>
33#include "gru.h"
34#include "grutables.h"
35#include "gruhandles.h"
36
Jack Steiner9ca8e40c12008-07-29 22:34:02 -070037unsigned long gru_options __read_mostly;
Jack Steiner9a0deec2008-07-29 22:33:58 -070038
39static struct device_driver gru_driver = {
40 .name = "gru"
41};
42
43static struct device gru_device = {
Kay Sieversbb0dc432009-01-06 10:44:37 -080044 .init_name = "",
Jack Steiner9a0deec2008-07-29 22:33:58 -070045 .driver = &gru_driver,
46};
47
48struct device *grudev = &gru_device;
49
50/*
51 * Select a gru fault map to be used by the current cpu. Note that
52 * multiple cpus may be using the same map.
Jack Steiner9a0deec2008-07-29 22:33:58 -070053 * ZZZ should be inline but did not work on emulator
54 */
55int gru_cpu_fault_map_id(void)
56{
Jack Steiner41314792009-12-15 16:48:15 -080057#ifdef CONFIG_IA64
58 return uv_blade_processor_id() % GRU_NUM_TFM;
59#else
Jack Steiner4107e1d2009-12-15 16:48:11 -080060 int cpu = smp_processor_id();
61 int id, core;
62
63 core = uv_cpu_core_number(cpu);
64 id = core + UV_MAX_INT_CORES * uv_cpu_socket_number(cpu);
65 return id;
Jack Steiner41314792009-12-15 16:48:15 -080066#endif
Jack Steiner9a0deec2008-07-29 22:33:58 -070067}
68
69/*--------- ASID Management -------------------------------------------
70 *
71 * Initially, assign asids sequentially from MIN_ASID .. MAX_ASID.
72 * Once MAX is reached, flush the TLB & start over. However,
73 * some asids may still be in use. There won't be many (percentage wise) still
74 * in use. Search active contexts & determine the value of the first
75 * asid in use ("x"s below). Set "limit" to this value.
76 * This defines a block of assignable asids.
77 *
78 * When "limit" is reached, search forward from limit+1 and determine the
79 * next block of assignable asids.
80 *
81 * Repeat until MAX_ASID is reached, then start over again.
82 *
83 * Each time MAX_ASID is reached, increment the asid generation. Since
84 * the search for in-use asids only checks contexts with GRUs currently
85 * assigned, asids in some contexts will be missed. Prior to loading
86 * a context, the asid generation of the GTS asid is rechecked. If it
87 * doesn't match the current generation, a new asid will be assigned.
88 *
89 * 0---------------x------------x---------------------x----|
90 * ^-next ^-limit ^-MAX_ASID
91 *
92 * All asid manipulation & context loading/unloading is protected by the
93 * gs_lock.
94 */
95
96/* Hit the asid limit. Start over */
97static int gru_wrap_asid(struct gru_state *gru)
98{
Jack Steiner43884602009-04-02 16:59:05 -070099 gru_dbg(grudev, "gid %d\n", gru->gs_gid);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700100 STAT(asid_wrap);
101 gru->gs_asid_gen++;
Jack Steiner9a0deec2008-07-29 22:33:58 -0700102 return MIN_ASID;
103}
104
105/* Find the next chunk of unused asids */
106static int gru_reset_asid_limit(struct gru_state *gru, int asid)
107{
108 int i, gid, inuse_asid, limit;
109
Jack Steiner43884602009-04-02 16:59:05 -0700110 gru_dbg(grudev, "gid %d, asid 0x%x\n", gru->gs_gid, asid);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700111 STAT(asid_next);
112 limit = MAX_ASID;
113 if (asid >= limit)
114 asid = gru_wrap_asid(gru);
Jack Steiner87419412009-04-02 16:59:08 -0700115 gru_flush_all_tlb(gru);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700116 gid = gru->gs_gid;
117again:
118 for (i = 0; i < GRU_NUM_CCH; i++) {
Jack Steiner836ce672009-06-17 16:28:22 -0700119 if (!gru->gs_gts[i] || is_kernel_context(gru->gs_gts[i]))
Jack Steiner9a0deec2008-07-29 22:33:58 -0700120 continue;
121 inuse_asid = gru->gs_gts[i]->ts_gms->ms_asids[gid].mt_asid;
Jack Steiner43884602009-04-02 16:59:05 -0700122 gru_dbg(grudev, "gid %d, gts %p, gms %p, inuse 0x%x, cxt %d\n",
123 gru->gs_gid, gru->gs_gts[i], gru->gs_gts[i]->ts_gms,
124 inuse_asid, i);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700125 if (inuse_asid == asid) {
126 asid += ASID_INC;
127 if (asid >= limit) {
128 /*
129 * empty range: reset the range limit and
130 * start over
131 */
132 limit = MAX_ASID;
133 if (asid >= MAX_ASID)
134 asid = gru_wrap_asid(gru);
135 goto again;
136 }
137 }
138
139 if ((inuse_asid > asid) && (inuse_asid < limit))
140 limit = inuse_asid;
141 }
142 gru->gs_asid_limit = limit;
143 gru->gs_asid = asid;
Jack Steiner43884602009-04-02 16:59:05 -0700144 gru_dbg(grudev, "gid %d, new asid 0x%x, new_limit 0x%x\n", gru->gs_gid,
145 asid, limit);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700146 return asid;
147}
148
149/* Assign a new ASID to a thread context. */
150static int gru_assign_asid(struct gru_state *gru)
151{
152 int asid;
153
Jack Steiner9a0deec2008-07-29 22:33:58 -0700154 gru->gs_asid += ASID_INC;
155 asid = gru->gs_asid;
156 if (asid >= gru->gs_asid_limit)
157 asid = gru_reset_asid_limit(gru, asid);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700158
Jack Steiner43884602009-04-02 16:59:05 -0700159 gru_dbg(grudev, "gid %d, asid 0x%x\n", gru->gs_gid, asid);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700160 return asid;
161}
162
163/*
164 * Clear n bits in a word. Return a word indicating the bits that were cleared.
165 * Optionally, build an array of chars that contain the bit numbers allocated.
166 */
167static unsigned long reserve_resources(unsigned long *p, int n, int mmax,
168 char *idx)
169{
170 unsigned long bits = 0;
171 int i;
172
Jack Steiner3eac2e92009-06-17 16:28:23 -0700173 while (n--) {
Jack Steiner9a0deec2008-07-29 22:33:58 -0700174 i = find_first_bit(p, mmax);
175 if (i == mmax)
176 BUG();
177 __clear_bit(i, p);
178 __set_bit(i, &bits);
179 if (idx)
180 *idx++ = i;
Jack Steiner3eac2e92009-06-17 16:28:23 -0700181 }
Jack Steiner9a0deec2008-07-29 22:33:58 -0700182 return bits;
183}
184
Jack Steiner9ca8e40c12008-07-29 22:34:02 -0700185unsigned long gru_reserve_cb_resources(struct gru_state *gru, int cbr_au_count,
Jack Steiner9a0deec2008-07-29 22:33:58 -0700186 char *cbmap)
187{
188 return reserve_resources(&gru->gs_cbr_map, cbr_au_count, GRU_CBR_AU,
189 cbmap);
190}
191
Jack Steiner9ca8e40c12008-07-29 22:34:02 -0700192unsigned long gru_reserve_ds_resources(struct gru_state *gru, int dsr_au_count,
Jack Steiner9a0deec2008-07-29 22:33:58 -0700193 char *dsmap)
194{
195 return reserve_resources(&gru->gs_dsr_map, dsr_au_count, GRU_DSR_AU,
196 dsmap);
197}
198
199static void reserve_gru_resources(struct gru_state *gru,
200 struct gru_thread_state *gts)
201{
202 gru->gs_active_contexts++;
203 gts->ts_cbr_map =
Jack Steiner9ca8e40c12008-07-29 22:34:02 -0700204 gru_reserve_cb_resources(gru, gts->ts_cbr_au_count,
Jack Steiner9a0deec2008-07-29 22:33:58 -0700205 gts->ts_cbr_idx);
206 gts->ts_dsr_map =
Jack Steiner9ca8e40c12008-07-29 22:34:02 -0700207 gru_reserve_ds_resources(gru, gts->ts_dsr_au_count, NULL);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700208}
209
210static void free_gru_resources(struct gru_state *gru,
211 struct gru_thread_state *gts)
212{
213 gru->gs_active_contexts--;
214 gru->gs_cbr_map |= gts->ts_cbr_map;
215 gru->gs_dsr_map |= gts->ts_dsr_map;
216}
217
218/*
219 * Check if a GRU has sufficient free resources to satisfy an allocation
220 * request. Note: GRU locks may or may not be held when this is called. If
221 * not held, recheck after acquiring the appropriate locks.
222 *
223 * Returns 1 if sufficient resources, 0 if not
224 */
225static int check_gru_resources(struct gru_state *gru, int cbr_au_count,
226 int dsr_au_count, int max_active_contexts)
227{
228 return hweight64(gru->gs_cbr_map) >= cbr_au_count
229 && hweight64(gru->gs_dsr_map) >= dsr_au_count
230 && gru->gs_active_contexts < max_active_contexts;
231}
232
233/*
234 * TLB manangment requires tracking all GRU chiplets that have loaded a GSEG
235 * context.
236 */
Jack Steiner43884602009-04-02 16:59:05 -0700237static int gru_load_mm_tracker(struct gru_state *gru,
238 struct gru_thread_state *gts)
Jack Steiner9a0deec2008-07-29 22:33:58 -0700239{
Jack Steiner43884602009-04-02 16:59:05 -0700240 struct gru_mm_struct *gms = gts->ts_gms;
Jack Steiner9a0deec2008-07-29 22:33:58 -0700241 struct gru_mm_tracker *asids = &gms->ms_asids[gru->gs_gid];
Jack Steiner43884602009-04-02 16:59:05 -0700242 unsigned short ctxbitmap = (1 << gts->ts_ctxnum);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700243 int asid;
244
245 spin_lock(&gms->ms_asid_lock);
246 asid = asids->mt_asid;
247
Jack Steiner87419412009-04-02 16:59:08 -0700248 spin_lock(&gru->gs_asid_lock);
249 if (asid == 0 || (asids->mt_ctxbitmap == 0 && asids->mt_asid_gen !=
250 gru->gs_asid_gen)) {
Jack Steiner9a0deec2008-07-29 22:33:58 -0700251 asid = gru_assign_asid(gru);
252 asids->mt_asid = asid;
253 asids->mt_asid_gen = gru->gs_asid_gen;
254 STAT(asid_new);
255 } else {
256 STAT(asid_reuse);
257 }
Jack Steiner87419412009-04-02 16:59:08 -0700258 spin_unlock(&gru->gs_asid_lock);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700259
260 BUG_ON(asids->mt_ctxbitmap & ctxbitmap);
261 asids->mt_ctxbitmap |= ctxbitmap;
262 if (!test_bit(gru->gs_gid, gms->ms_asidmap))
263 __set_bit(gru->gs_gid, gms->ms_asidmap);
264 spin_unlock(&gms->ms_asid_lock);
265
266 gru_dbg(grudev,
Jack Steiner43884602009-04-02 16:59:05 -0700267 "gid %d, gts %p, gms %p, ctxnum %d, asid 0x%x, asidmap 0x%lx\n",
268 gru->gs_gid, gts, gms, gts->ts_ctxnum, asid,
269 gms->ms_asidmap[0]);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700270 return asid;
271}
272
273static void gru_unload_mm_tracker(struct gru_state *gru,
Jack Steiner43884602009-04-02 16:59:05 -0700274 struct gru_thread_state *gts)
Jack Steiner9a0deec2008-07-29 22:33:58 -0700275{
Jack Steiner43884602009-04-02 16:59:05 -0700276 struct gru_mm_struct *gms = gts->ts_gms;
Jack Steiner9a0deec2008-07-29 22:33:58 -0700277 struct gru_mm_tracker *asids;
278 unsigned short ctxbitmap;
279
280 asids = &gms->ms_asids[gru->gs_gid];
Jack Steiner43884602009-04-02 16:59:05 -0700281 ctxbitmap = (1 << gts->ts_ctxnum);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700282 spin_lock(&gms->ms_asid_lock);
Jack Steiner87419412009-04-02 16:59:08 -0700283 spin_lock(&gru->gs_asid_lock);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700284 BUG_ON((asids->mt_ctxbitmap & ctxbitmap) != ctxbitmap);
285 asids->mt_ctxbitmap ^= ctxbitmap;
Jack Steiner43884602009-04-02 16:59:05 -0700286 gru_dbg(grudev, "gid %d, gts %p, gms %p, ctxnum 0x%d, asidmap 0x%lx\n",
287 gru->gs_gid, gts, gms, gts->ts_ctxnum, gms->ms_asidmap[0]);
Jack Steiner87419412009-04-02 16:59:08 -0700288 spin_unlock(&gru->gs_asid_lock);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700289 spin_unlock(&gms->ms_asid_lock);
290}
291
292/*
293 * Decrement the reference count on a GTS structure. Free the structure
294 * if the reference count goes to zero.
295 */
296void gts_drop(struct gru_thread_state *gts)
297{
298 if (gts && atomic_dec_return(&gts->ts_refcnt) == 0) {
Jack Steiner7f2251b2009-12-15 16:48:08 -0800299 if (gts->ts_gms)
300 gru_drop_mmu_notifier(gts->ts_gms);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700301 kfree(gts);
302 STAT(gts_free);
303 }
304}
305
306/*
307 * Locate the GTS structure for the current thread.
308 */
309static struct gru_thread_state *gru_find_current_gts_nolock(struct gru_vma_data
310 *vdata, int tsid)
311{
312 struct gru_thread_state *gts;
313
314 list_for_each_entry(gts, &vdata->vd_head, ts_next)
315 if (gts->ts_tsid == tsid)
316 return gts;
317 return NULL;
318}
319
320/*
321 * Allocate a thread state structure.
322 */
Jack Steiner364b76d2009-06-17 16:28:20 -0700323struct gru_thread_state *gru_alloc_gts(struct vm_area_struct *vma,
Jack Steinerc5502222009-12-15 16:48:13 -0800324 int cbr_au_count, int dsr_au_count,
325 unsigned char tlb_preload_count, int options, int tsid)
Jack Steiner9a0deec2008-07-29 22:33:58 -0700326{
327 struct gru_thread_state *gts;
Jack Steiner7f2251b2009-12-15 16:48:08 -0800328 struct gru_mm_struct *gms;
Jack Steiner9a0deec2008-07-29 22:33:58 -0700329 int bytes;
330
Jack Steiner364b76d2009-06-17 16:28:20 -0700331 bytes = DSR_BYTES(dsr_au_count) + CBR_BYTES(cbr_au_count);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700332 bytes += sizeof(struct gru_thread_state);
Jack Steiner940229b2009-06-17 16:28:24 -0700333 gts = kmalloc(bytes, GFP_KERNEL);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700334 if (!gts)
Jack Steiner7f2251b2009-12-15 16:48:08 -0800335 return ERR_PTR(-ENOMEM);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700336
337 STAT(gts_alloc);
Jack Steiner940229b2009-06-17 16:28:24 -0700338 memset(gts, 0, sizeof(struct gru_thread_state)); /* zero out header */
Jack Steiner9a0deec2008-07-29 22:33:58 -0700339 atomic_set(&gts->ts_refcnt, 1);
340 mutex_init(&gts->ts_ctxlock);
Jack Steiner364b76d2009-06-17 16:28:20 -0700341 gts->ts_cbr_au_count = cbr_au_count;
342 gts->ts_dsr_au_count = dsr_au_count;
Jack Steinerc5502222009-12-15 16:48:13 -0800343 gts->ts_tlb_preload_count = tlb_preload_count;
Jack Steiner364b76d2009-06-17 16:28:20 -0700344 gts->ts_user_options = options;
Jack Steiner518e5cd2009-12-15 16:48:04 -0800345 gts->ts_user_blade_id = -1;
346 gts->ts_user_chiplet_id = -1;
Jack Steiner9a0deec2008-07-29 22:33:58 -0700347 gts->ts_tsid = tsid;
Jack Steiner9a0deec2008-07-29 22:33:58 -0700348 gts->ts_ctxnum = NULLCTX;
Jack Steiner9a0deec2008-07-29 22:33:58 -0700349 gts->ts_tlb_int_select = -1;
Jack Steinerb1b19fc2009-06-17 16:28:33 -0700350 gts->ts_cch_req_slice = -1;
Jack Steiner7b8274e2009-04-02 16:59:12 -0700351 gts->ts_sizeavail = GRU_SIZEAVAIL(PAGE_SHIFT);
Jack Steiner364b76d2009-06-17 16:28:20 -0700352 if (vma) {
353 gts->ts_mm = current->mm;
354 gts->ts_vma = vma;
Jack Steiner7f2251b2009-12-15 16:48:08 -0800355 gms = gru_register_mmu_notifier();
356 if (IS_ERR(gms))
Jack Steiner364b76d2009-06-17 16:28:20 -0700357 goto err;
Jack Steiner7f2251b2009-12-15 16:48:08 -0800358 gts->ts_gms = gms;
Jack Steiner364b76d2009-06-17 16:28:20 -0700359 }
Jack Steiner9a0deec2008-07-29 22:33:58 -0700360
Jack Steiner364b76d2009-06-17 16:28:20 -0700361 gru_dbg(grudev, "alloc gts %p\n", gts);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700362 return gts;
363
364err:
365 gts_drop(gts);
Jack Steiner7f2251b2009-12-15 16:48:08 -0800366 return ERR_CAST(gms);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700367}
368
369/*
370 * Allocate a vma private data structure.
371 */
372struct gru_vma_data *gru_alloc_vma_data(struct vm_area_struct *vma, int tsid)
373{
374 struct gru_vma_data *vdata = NULL;
375
376 vdata = kmalloc(sizeof(*vdata), GFP_KERNEL);
377 if (!vdata)
378 return NULL;
379
Jack Steiner563447d2009-12-15 16:48:12 -0800380 STAT(vdata_alloc);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700381 INIT_LIST_HEAD(&vdata->vd_head);
382 spin_lock_init(&vdata->vd_lock);
383 gru_dbg(grudev, "alloc vdata %p\n", vdata);
384 return vdata;
385}
386
387/*
388 * Find the thread state structure for the current thread.
389 */
390struct gru_thread_state *gru_find_thread_state(struct vm_area_struct *vma,
391 int tsid)
392{
393 struct gru_vma_data *vdata = vma->vm_private_data;
394 struct gru_thread_state *gts;
395
396 spin_lock(&vdata->vd_lock);
397 gts = gru_find_current_gts_nolock(vdata, tsid);
398 spin_unlock(&vdata->vd_lock);
399 gru_dbg(grudev, "vma %p, gts %p\n", vma, gts);
400 return gts;
401}
402
403/*
404 * Allocate a new thread state for a GSEG. Note that races may allow
405 * another thread to race to create a gts.
406 */
407struct gru_thread_state *gru_alloc_thread_state(struct vm_area_struct *vma,
408 int tsid)
409{
410 struct gru_vma_data *vdata = vma->vm_private_data;
411 struct gru_thread_state *gts, *ngts;
412
Jack Steinerc5502222009-12-15 16:48:13 -0800413 gts = gru_alloc_gts(vma, vdata->vd_cbr_au_count,
414 vdata->vd_dsr_au_count,
415 vdata->vd_tlb_preload_count,
Jack Steiner364b76d2009-06-17 16:28:20 -0700416 vdata->vd_user_options, tsid);
Jack Steiner7f2251b2009-12-15 16:48:08 -0800417 if (IS_ERR(gts))
418 return gts;
Jack Steiner9a0deec2008-07-29 22:33:58 -0700419
420 spin_lock(&vdata->vd_lock);
421 ngts = gru_find_current_gts_nolock(vdata, tsid);
422 if (ngts) {
423 gts_drop(gts);
424 gts = ngts;
425 STAT(gts_double_allocate);
426 } else {
427 list_add(&gts->ts_next, &vdata->vd_head);
428 }
429 spin_unlock(&vdata->vd_lock);
430 gru_dbg(grudev, "vma %p, gts %p\n", vma, gts);
431 return gts;
432}
433
434/*
435 * Free the GRU context assigned to the thread state.
436 */
437static void gru_free_gru_context(struct gru_thread_state *gts)
438{
439 struct gru_state *gru;
440
441 gru = gts->ts_gru;
Jack Steiner43884602009-04-02 16:59:05 -0700442 gru_dbg(grudev, "gts %p, gid %d\n", gts, gru->gs_gid);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700443
444 spin_lock(&gru->gs_lock);
445 gru->gs_gts[gts->ts_ctxnum] = NULL;
446 free_gru_resources(gru, gts);
447 BUG_ON(test_bit(gts->ts_ctxnum, &gru->gs_context_map) == 0);
448 __clear_bit(gts->ts_ctxnum, &gru->gs_context_map);
449 gts->ts_ctxnum = NULLCTX;
450 gts->ts_gru = NULL;
Jack Steiner87419412009-04-02 16:59:08 -0700451 gts->ts_blade = -1;
Jack Steiner9a0deec2008-07-29 22:33:58 -0700452 spin_unlock(&gru->gs_lock);
453
454 gts_drop(gts);
455 STAT(free_context);
456}
457
458/*
459 * Prefetching cachelines help hardware performance.
Jack Steiner9ca8e40c12008-07-29 22:34:02 -0700460 * (Strictly a performance enhancement. Not functionally required).
Jack Steiner9a0deec2008-07-29 22:33:58 -0700461 */
462static void prefetch_data(void *p, int num, int stride)
463{
464 while (num-- > 0) {
465 prefetchw(p);
466 p += stride;
467 }
468}
469
470static inline long gru_copy_handle(void *d, void *s)
471{
472 memcpy(d, s, GRU_HANDLE_BYTES);
473 return GRU_HANDLE_BYTES;
474}
475
Jack Steinerfe5bb6b2009-04-02 16:59:04 -0700476static void gru_prefetch_context(void *gseg, void *cb, void *cbe,
477 unsigned long cbrmap, unsigned long length)
Jack Steiner923f7f62008-10-15 22:05:13 -0700478{
479 int i, scr;
480
481 prefetch_data(gseg + GRU_DS_BASE, length / GRU_CACHE_LINE_BYTES,
482 GRU_CACHE_LINE_BYTES);
483
484 for_each_cbr_in_allocation_map(i, &cbrmap, scr) {
485 prefetch_data(cb, 1, GRU_CACHE_LINE_BYTES);
486 prefetch_data(cbe + i * GRU_HANDLE_STRIDE, 1,
487 GRU_CACHE_LINE_BYTES);
488 cb += GRU_HANDLE_STRIDE;
489 }
490}
491
Jack Steiner9a0deec2008-07-29 22:33:58 -0700492static void gru_load_context_data(void *save, void *grubase, int ctxnum,
Jack Steiner940229b2009-06-17 16:28:24 -0700493 unsigned long cbrmap, unsigned long dsrmap,
494 int data_valid)
Jack Steiner9a0deec2008-07-29 22:33:58 -0700495{
496 void *gseg, *cb, *cbe;
497 unsigned long length;
498 int i, scr;
499
500 gseg = grubase + ctxnum * GRU_GSEG_STRIDE;
Jack Steiner9a0deec2008-07-29 22:33:58 -0700501 cb = gseg + GRU_CB_BASE;
502 cbe = grubase + GRU_CBE_BASE;
Jack Steiner923f7f62008-10-15 22:05:13 -0700503 length = hweight64(dsrmap) * GRU_DSR_AU_BYTES;
504 gru_prefetch_context(gseg, cb, cbe, cbrmap, length);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700505
Jack Steiner9a0deec2008-07-29 22:33:58 -0700506 for_each_cbr_in_allocation_map(i, &cbrmap, scr) {
Jack Steiner940229b2009-06-17 16:28:24 -0700507 if (data_valid) {
508 save += gru_copy_handle(cb, save);
509 save += gru_copy_handle(cbe + i * GRU_HANDLE_STRIDE,
510 save);
511 } else {
512 memset(cb, 0, GRU_CACHE_LINE_BYTES);
513 memset(cbe + i * GRU_HANDLE_STRIDE, 0,
514 GRU_CACHE_LINE_BYTES);
515 }
Jack Steiner67bf04a2009-12-15 16:48:11 -0800516 /* Flush CBE to hide race in context restart */
517 mb();
518 gru_flush_cache(cbe + i * GRU_HANDLE_STRIDE);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700519 cb += GRU_HANDLE_STRIDE;
520 }
521
Jack Steiner940229b2009-06-17 16:28:24 -0700522 if (data_valid)
523 memcpy(gseg + GRU_DS_BASE, save, length);
524 else
525 memset(gseg + GRU_DS_BASE, 0, length);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700526}
527
528static void gru_unload_context_data(void *save, void *grubase, int ctxnum,
529 unsigned long cbrmap, unsigned long dsrmap)
530{
531 void *gseg, *cb, *cbe;
532 unsigned long length;
533 int i, scr;
534
535 gseg = grubase + ctxnum * GRU_GSEG_STRIDE;
Jack Steiner9a0deec2008-07-29 22:33:58 -0700536 cb = gseg + GRU_CB_BASE;
537 cbe = grubase + GRU_CBE_BASE;
Jack Steiner923f7f62008-10-15 22:05:13 -0700538 length = hweight64(dsrmap) * GRU_DSR_AU_BYTES;
Jack Steiner67bf04a2009-12-15 16:48:11 -0800539
540 /* CBEs may not be coherent. Flush them from cache */
541 for_each_cbr_in_allocation_map(i, &cbrmap, scr)
542 gru_flush_cache(cbe + i * GRU_HANDLE_STRIDE);
543 mb(); /* Let the CL flush complete */
544
Jack Steiner923f7f62008-10-15 22:05:13 -0700545 gru_prefetch_context(gseg, cb, cbe, cbrmap, length);
546
Jack Steiner9a0deec2008-07-29 22:33:58 -0700547 for_each_cbr_in_allocation_map(i, &cbrmap, scr) {
548 save += gru_copy_handle(save, cb);
549 save += gru_copy_handle(save, cbe + i * GRU_HANDLE_STRIDE);
550 cb += GRU_HANDLE_STRIDE;
551 }
Jack Steiner9a0deec2008-07-29 22:33:58 -0700552 memcpy(save, gseg + GRU_DS_BASE, length);
553}
554
555void gru_unload_context(struct gru_thread_state *gts, int savestate)
556{
557 struct gru_state *gru = gts->ts_gru;
558 struct gru_context_configuration_handle *cch;
559 int ctxnum = gts->ts_ctxnum;
560
Jack Steiner836ce672009-06-17 16:28:22 -0700561 if (!is_kernel_context(gts))
562 zap_vma_ptes(gts->ts_vma, UGRUADDR(gts), GRU_GSEG_PAGESIZE);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700563 cch = get_cch(gru->gs_gru_base_vaddr, ctxnum);
564
Jack Steiner563447d2009-12-15 16:48:12 -0800565 gru_dbg(grudev, "gts %p, cbrmap 0x%lx, dsrmap 0x%lx\n",
566 gts, gts->ts_cbr_map, gts->ts_dsr_map);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700567 lock_cch_handle(cch);
568 if (cch_interrupt_sync(cch))
569 BUG();
Jack Steiner9a0deec2008-07-29 22:33:58 -0700570
Jack Steiner836ce672009-06-17 16:28:22 -0700571 if (!is_kernel_context(gts))
572 gru_unload_mm_tracker(gru, gts);
Jack Steiner940229b2009-06-17 16:28:24 -0700573 if (savestate) {
Jack Steiner9a0deec2008-07-29 22:33:58 -0700574 gru_unload_context_data(gts->ts_gdata, gru->gs_gru_base_vaddr,
575 ctxnum, gts->ts_cbr_map,
576 gts->ts_dsr_map);
Jack Steiner940229b2009-06-17 16:28:24 -0700577 gts->ts_data_valid = 1;
578 }
Jack Steiner9a0deec2008-07-29 22:33:58 -0700579
580 if (cch_deallocate(cch))
581 BUG();
Jack Steiner9a0deec2008-07-29 22:33:58 -0700582 unlock_cch_handle(cch);
583
584 gru_free_gru_context(gts);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700585}
586
587/*
588 * Load a GRU context by copying it from the thread data structure in memory
589 * to the GRU.
590 */
Jack Steinerd57c82b2009-06-17 16:28:20 -0700591void gru_load_context(struct gru_thread_state *gts)
Jack Steiner9a0deec2008-07-29 22:33:58 -0700592{
593 struct gru_state *gru = gts->ts_gru;
594 struct gru_context_configuration_handle *cch;
Jack Steiner6e910072009-06-17 16:28:21 -0700595 int i, err, asid, ctxnum = gts->ts_ctxnum;
Jack Steiner9a0deec2008-07-29 22:33:58 -0700596
Jack Steiner9a0deec2008-07-29 22:33:58 -0700597 cch = get_cch(gru->gs_gru_base_vaddr, ctxnum);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700598 lock_cch_handle(cch);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700599 cch->tfm_fault_bit_enable =
600 (gts->ts_user_options == GRU_OPT_MISS_FMM_POLL
601 || gts->ts_user_options == GRU_OPT_MISS_FMM_INTR);
602 cch->tlb_int_enable = (gts->ts_user_options == GRU_OPT_MISS_FMM_INTR);
603 if (cch->tlb_int_enable) {
604 gts->ts_tlb_int_select = gru_cpu_fault_map_id();
605 cch->tlb_int_select = gts->ts_tlb_int_select;
606 }
Jack Steinerb1b19fc2009-06-17 16:28:33 -0700607 if (gts->ts_cch_req_slice >= 0) {
608 cch->req_slice_set_enable = 1;
609 cch->req_slice = gts->ts_cch_req_slice;
610 } else {
611 cch->req_slice_set_enable =0;
612 }
Jack Steiner9a0deec2008-07-29 22:33:58 -0700613 cch->tfm_done_bit_enable = 0;
Jack Steiner6e910072009-06-17 16:28:21 -0700614 cch->dsr_allocation_map = gts->ts_dsr_map;
615 cch->cbr_allocation_map = gts->ts_cbr_map;
Jack Steiner836ce672009-06-17 16:28:22 -0700616
617 if (is_kernel_context(gts)) {
618 cch->unmap_enable = 1;
Jack Steiner4a7a17c2009-06-17 16:28:25 -0700619 cch->tfm_done_bit_enable = 1;
620 cch->cb_int_enable = 1;
Jack Steiner4107e1d2009-12-15 16:48:11 -0800621 cch->tlb_int_select = 0; /* For now, ints go to cpu 0 */
Jack Steiner836ce672009-06-17 16:28:22 -0700622 } else {
623 cch->unmap_enable = 0;
Jack Steiner4a7a17c2009-06-17 16:28:25 -0700624 cch->tfm_done_bit_enable = 0;
625 cch->cb_int_enable = 0;
Jack Steiner836ce672009-06-17 16:28:22 -0700626 asid = gru_load_mm_tracker(gru, gts);
627 for (i = 0; i < 8; i++) {
628 cch->asid[i] = asid + i;
629 cch->sizeavail[i] = gts->ts_sizeavail;
630 }
Jack Steiner6e910072009-06-17 16:28:21 -0700631 }
632
633 err = cch_allocate(cch);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700634 if (err) {
635 gru_dbg(grudev,
636 "err %d: cch %p, gts %p, cbr 0x%lx, dsr 0x%lx\n",
637 err, cch, gts, gts->ts_cbr_map, gts->ts_dsr_map);
638 BUG();
639 }
640
641 gru_load_context_data(gts->ts_gdata, gru->gs_gru_base_vaddr, ctxnum,
Jack Steiner940229b2009-06-17 16:28:24 -0700642 gts->ts_cbr_map, gts->ts_dsr_map, gts->ts_data_valid);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700643
644 if (cch_start(cch))
645 BUG();
646 unlock_cch_handle(cch);
Jack Steiner563447d2009-12-15 16:48:12 -0800647
648 gru_dbg(grudev, "gid %d, gts %p, cbrmap 0x%lx, dsrmap 0x%lx, tie %d, tis %d\n",
649 gts->ts_gru->gs_gid, gts, gts->ts_cbr_map, gts->ts_dsr_map,
650 (gts->ts_user_options == GRU_OPT_MISS_FMM_INTR), gts->ts_tlb_int_select);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700651}
652
653/*
654 * Update fields in an active CCH:
655 * - retarget interrupts on local blade
Jack Steiner7b8274e2009-04-02 16:59:12 -0700656 * - update sizeavail mask
Jack Steiner9a0deec2008-07-29 22:33:58 -0700657 */
Jack Steiner99f7c222009-12-15 16:48:06 -0800658int gru_update_cch(struct gru_thread_state *gts)
Jack Steiner9a0deec2008-07-29 22:33:58 -0700659{
660 struct gru_context_configuration_handle *cch;
661 struct gru_state *gru = gts->ts_gru;
662 int i, ctxnum = gts->ts_ctxnum, ret = 0;
663
664 cch = get_cch(gru->gs_gru_base_vaddr, ctxnum);
665
666 lock_cch_handle(cch);
667 if (cch->state == CCHSTATE_ACTIVE) {
668 if (gru->gs_gts[gts->ts_ctxnum] != gts)
669 goto exit;
670 if (cch_interrupt(cch))
671 BUG();
Jack Steiner99f7c222009-12-15 16:48:06 -0800672 for (i = 0; i < 8; i++)
673 cch->sizeavail[i] = gts->ts_sizeavail;
674 gts->ts_tlb_int_select = gru_cpu_fault_map_id();
675 cch->tlb_int_select = gru_cpu_fault_map_id();
676 cch->tfm_fault_bit_enable =
677 (gts->ts_user_options == GRU_OPT_MISS_FMM_POLL
678 || gts->ts_user_options == GRU_OPT_MISS_FMM_INTR);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700679 if (cch_start(cch))
680 BUG();
681 ret = 1;
682 }
683exit:
684 unlock_cch_handle(cch);
685 return ret;
686}
687
688/*
689 * Update CCH tlb interrupt select. Required when all the following is true:
690 * - task's GRU context is loaded into a GRU
691 * - task is using interrupt notification for TLB faults
692 * - task has migrated to a different cpu on the same blade where
693 * it was previously running.
694 */
695static int gru_retarget_intr(struct gru_thread_state *gts)
696{
697 if (gts->ts_tlb_int_select < 0
698 || gts->ts_tlb_int_select == gru_cpu_fault_map_id())
699 return 0;
700
701 gru_dbg(grudev, "retarget from %d to %d\n", gts->ts_tlb_int_select,
702 gru_cpu_fault_map_id());
Jack Steiner99f7c222009-12-15 16:48:06 -0800703 return gru_update_cch(gts);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700704}
705
Jack Steiner55484c42009-12-15 16:48:05 -0800706/*
Jack Steiner41314792009-12-15 16:48:15 -0800707 * Check if a GRU context is allowed to use a specific chiplet. By default
708 * a context is assigned to any blade-local chiplet. However, users can
709 * override this.
710 * Returns 1 if assignment allowed, 0 otherwise
711 */
712static int gru_check_chiplet_assignment(struct gru_state *gru,
713 struct gru_thread_state *gts)
714{
715 int blade_id;
716 int chiplet_id;
717
718 blade_id = gts->ts_user_blade_id;
719 if (blade_id < 0)
720 blade_id = uv_numa_blade_id();
721
722 chiplet_id = gts->ts_user_chiplet_id;
723 return gru->gs_blade_id == blade_id &&
724 (chiplet_id < 0 || chiplet_id == gru->gs_chiplet_id);
725}
726
727/*
Jack Steiner55484c42009-12-15 16:48:05 -0800728 * Unload the gru context if it is not assigned to the correct blade or
729 * chiplet. Misassignment can occur if the process migrates to a different
730 * blade or if the user changes the selected blade/chiplet.
Jack Steiner55484c42009-12-15 16:48:05 -0800731 */
732void gru_check_context_placement(struct gru_thread_state *gts)
733{
734 struct gru_state *gru;
Jack Steiner55484c42009-12-15 16:48:05 -0800735
736 /*
737 * If the current task is the context owner, verify that the
738 * context is correctly placed. This test is skipped for non-owner
739 * references. Pthread apps use non-owner references to the CBRs.
740 */
741 gru = gts->ts_gru;
742 if (!gru || gts->ts_tgid_owner != current->tgid)
743 return;
744
Jack Steiner41314792009-12-15 16:48:15 -0800745 if (!gru_check_chiplet_assignment(gru, gts)) {
Jack Steiner55484c42009-12-15 16:48:05 -0800746 STAT(check_context_unload);
747 gru_unload_context(gts, 1);
748 } else if (gru_retarget_intr(gts)) {
749 STAT(check_context_retarget_intr);
750 }
751}
752
Jack Steiner9a0deec2008-07-29 22:33:58 -0700753
754/*
755 * Insufficient GRU resources available on the local blade. Steal a context from
756 * a process. This is a hack until a _real_ resource scheduler is written....
757 */
758#define next_ctxnum(n) ((n) < GRU_NUM_CCH - 2 ? (n) + 1 : 0)
759#define next_gru(b, g) (((g) < &(b)->bs_grus[GRU_CHIPLETS_PER_BLADE - 1]) ? \
760 ((g)+1) : &(b)->bs_grus[0])
761
Jack Steiner836ce672009-06-17 16:28:22 -0700762static int is_gts_stealable(struct gru_thread_state *gts,
763 struct gru_blade_state *bs)
764{
765 if (is_kernel_context(gts))
766 return down_write_trylock(&bs->bs_kgts_sema);
767 else
768 return mutex_trylock(&gts->ts_ctxlock);
769}
770
771static void gts_stolen(struct gru_thread_state *gts,
772 struct gru_blade_state *bs)
773{
774 if (is_kernel_context(gts)) {
775 up_write(&bs->bs_kgts_sema);
776 STAT(steal_kernel_context);
777 } else {
778 mutex_unlock(&gts->ts_ctxlock);
779 STAT(steal_user_context);
780 }
781}
782
Jack Steiner55484c42009-12-15 16:48:05 -0800783void gru_steal_context(struct gru_thread_state *gts)
Jack Steiner9a0deec2008-07-29 22:33:58 -0700784{
785 struct gru_blade_state *blade;
786 struct gru_state *gru, *gru0;
787 struct gru_thread_state *ngts = NULL;
788 int ctxnum, ctxnum0, flag = 0, cbr, dsr;
Jack Steiner41314792009-12-15 16:48:15 -0800789 int blade_id;
Jack Steiner9a0deec2008-07-29 22:33:58 -0700790
Jack Steiner41314792009-12-15 16:48:15 -0800791 blade_id = gts->ts_user_blade_id;
Jack Steiner55484c42009-12-15 16:48:05 -0800792 if (blade_id < 0)
793 blade_id = uv_numa_blade_id();
Jack Steiner9a0deec2008-07-29 22:33:58 -0700794 cbr = gts->ts_cbr_au_count;
795 dsr = gts->ts_dsr_au_count;
796
Jack Steiner364b76d2009-06-17 16:28:20 -0700797 blade = gru_base[blade_id];
Jack Steiner9a0deec2008-07-29 22:33:58 -0700798 spin_lock(&blade->bs_lock);
799
800 ctxnum = next_ctxnum(blade->bs_lru_ctxnum);
801 gru = blade->bs_lru_gru;
802 if (ctxnum == 0)
803 gru = next_gru(blade, gru);
Jack Steiner55484c42009-12-15 16:48:05 -0800804 blade->bs_lru_gru = gru;
805 blade->bs_lru_ctxnum = ctxnum;
Jack Steiner9a0deec2008-07-29 22:33:58 -0700806 ctxnum0 = ctxnum;
807 gru0 = gru;
808 while (1) {
Jack Steiner41314792009-12-15 16:48:15 -0800809 if (gru_check_chiplet_assignment(gru, gts)) {
Jack Steiner55484c42009-12-15 16:48:05 -0800810 if (check_gru_resources(gru, cbr, dsr, GRU_NUM_CCH))
Jack Steiner9a0deec2008-07-29 22:33:58 -0700811 break;
Jack Steiner55484c42009-12-15 16:48:05 -0800812 spin_lock(&gru->gs_lock);
813 for (; ctxnum < GRU_NUM_CCH; ctxnum++) {
814 if (flag && gru == gru0 && ctxnum == ctxnum0)
815 break;
816 ngts = gru->gs_gts[ctxnum];
817 /*
818 * We are grabbing locks out of order, so trylock is
819 * needed. GTSs are usually not locked, so the odds of
820 * success are high. If trylock fails, try to steal a
821 * different GSEG.
822 */
823 if (ngts && is_gts_stealable(ngts, blade))
824 break;
825 ngts = NULL;
826 }
827 spin_unlock(&gru->gs_lock);
828 if (ngts || (flag && gru == gru0 && ctxnum == ctxnum0))
Jack Steiner9a0deec2008-07-29 22:33:58 -0700829 break;
Jack Steiner9a0deec2008-07-29 22:33:58 -0700830 }
Jack Steiner55484c42009-12-15 16:48:05 -0800831 if (flag && gru == gru0)
Jack Steiner9a0deec2008-07-29 22:33:58 -0700832 break;
Jack Steiner55484c42009-12-15 16:48:05 -0800833 flag = 1;
Jack Steiner9a0deec2008-07-29 22:33:58 -0700834 ctxnum = 0;
835 gru = next_gru(blade, gru);
836 }
Jack Steiner9a0deec2008-07-29 22:33:58 -0700837 spin_unlock(&blade->bs_lock);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700838
839 if (ngts) {
Jack Steiner7e796a72009-06-17 16:28:30 -0700840 gts->ustats.context_stolen++;
Jack Steiner9a0deec2008-07-29 22:33:58 -0700841 ngts->ts_steal_jiffies = jiffies;
Jack Steiner836ce672009-06-17 16:28:22 -0700842 gru_unload_context(ngts, is_kernel_context(ngts) ? 0 : 1);
843 gts_stolen(ngts, blade);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700844 } else {
845 STAT(steal_context_failed);
846 }
847 gru_dbg(grudev,
Jack Steiner43884602009-04-02 16:59:05 -0700848 "stole gid %d, ctxnum %d from gts %p. Need cb %d, ds %d;"
Jack Steiner9a0deec2008-07-29 22:33:58 -0700849 " avail cb %ld, ds %ld\n",
850 gru->gs_gid, ctxnum, ngts, cbr, dsr, hweight64(gru->gs_cbr_map),
851 hweight64(gru->gs_dsr_map));
852}
853
854/*
Jack Steiner55484c42009-12-15 16:48:05 -0800855 * Assign a gru context.
856 */
857static int gru_assign_context_number(struct gru_state *gru)
858{
859 int ctxnum;
860
861 ctxnum = find_first_zero_bit(&gru->gs_context_map, GRU_NUM_CCH);
862 __set_bit(ctxnum, &gru->gs_context_map);
863 return ctxnum;
864}
865
866/*
Jack Steiner9a0deec2008-07-29 22:33:58 -0700867 * Scan the GRUs on the local blade & assign a GRU context.
868 */
Jack Steiner55484c42009-12-15 16:48:05 -0800869struct gru_state *gru_assign_gru_context(struct gru_thread_state *gts)
Jack Steiner9a0deec2008-07-29 22:33:58 -0700870{
871 struct gru_state *gru, *grux;
872 int i, max_active_contexts;
Jack Steiner55484c42009-12-15 16:48:05 -0800873 int blade_id = gts->ts_user_blade_id;
Jack Steiner9a0deec2008-07-29 22:33:58 -0700874
Jack Steiner55484c42009-12-15 16:48:05 -0800875 if (blade_id < 0)
876 blade_id = uv_numa_blade_id();
Jack Steiner9a0deec2008-07-29 22:33:58 -0700877again:
878 gru = NULL;
879 max_active_contexts = GRU_NUM_CCH;
Jack Steiner55484c42009-12-15 16:48:05 -0800880 for_each_gru_on_blade(grux, blade_id, i) {
Jack Steiner41314792009-12-15 16:48:15 -0800881 if (!gru_check_chiplet_assignment(grux, gts))
Jack Steiner55484c42009-12-15 16:48:05 -0800882 continue;
Jack Steiner9a0deec2008-07-29 22:33:58 -0700883 if (check_gru_resources(grux, gts->ts_cbr_au_count,
884 gts->ts_dsr_au_count,
885 max_active_contexts)) {
886 gru = grux;
887 max_active_contexts = grux->gs_active_contexts;
888 if (max_active_contexts == 0)
889 break;
890 }
891 }
892
893 if (gru) {
894 spin_lock(&gru->gs_lock);
895 if (!check_gru_resources(gru, gts->ts_cbr_au_count,
896 gts->ts_dsr_au_count, GRU_NUM_CCH)) {
897 spin_unlock(&gru->gs_lock);
898 goto again;
899 }
900 reserve_gru_resources(gru, gts);
901 gts->ts_gru = gru;
Jack Steiner87419412009-04-02 16:59:08 -0700902 gts->ts_blade = gru->gs_blade_id;
Jack Steiner55484c42009-12-15 16:48:05 -0800903 gts->ts_ctxnum = gru_assign_context_number(gru);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700904 atomic_inc(&gts->ts_refcnt);
905 gru->gs_gts[gts->ts_ctxnum] = gts;
Jack Steiner9a0deec2008-07-29 22:33:58 -0700906 spin_unlock(&gru->gs_lock);
907
908 STAT(assign_context);
909 gru_dbg(grudev,
Jack Steiner43884602009-04-02 16:59:05 -0700910 "gseg %p, gts %p, gid %d, ctx %d, cbr %d, dsr %d\n",
Jack Steiner9a0deec2008-07-29 22:33:58 -0700911 gseg_virtual_address(gts->ts_gru, gts->ts_ctxnum), gts,
912 gts->ts_gru->gs_gid, gts->ts_ctxnum,
913 gts->ts_cbr_au_count, gts->ts_dsr_au_count);
914 } else {
915 gru_dbg(grudev, "failed to allocate a GTS %s\n", "");
916 STAT(assign_context_failed);
917 }
918
Jack Steiner9a0deec2008-07-29 22:33:58 -0700919 return gru;
920}
921
922/*
923 * gru_nopage
924 *
925 * Map the user's GRU segment
Jack Steiner9ca8e40c12008-07-29 22:34:02 -0700926 *
927 * Note: gru segments alway mmaped on GRU_GSEG_PAGESIZE boundaries.
Jack Steiner9a0deec2008-07-29 22:33:58 -0700928 */
929int gru_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
930{
931 struct gru_thread_state *gts;
932 unsigned long paddr, vaddr;
933
934 vaddr = (unsigned long)vmf->virtual_address;
935 gru_dbg(grudev, "vma %p, vaddr 0x%lx (0x%lx)\n",
936 vma, vaddr, GSEG_BASE(vaddr));
937 STAT(nopfn);
938
Jack Steiner9ca8e40c12008-07-29 22:34:02 -0700939 /* The following check ensures vaddr is a valid address in the VMA */
Jack Steiner9a0deec2008-07-29 22:33:58 -0700940 gts = gru_find_thread_state(vma, TSID(vaddr, vma));
941 if (!gts)
942 return VM_FAULT_SIGBUS;
943
944again:
Jack Steiner9a0deec2008-07-29 22:33:58 -0700945 mutex_lock(&gts->ts_ctxlock);
Jack Steinerfe5bb6b2009-04-02 16:59:04 -0700946 preempt_disable();
Jack Steiner364b76d2009-06-17 16:28:20 -0700947
Jack Steiner55484c42009-12-15 16:48:05 -0800948 gru_check_context_placement(gts);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700949
950 if (!gts->ts_gru) {
Jack Steiner836ce672009-06-17 16:28:22 -0700951 STAT(load_user_context);
Jack Steiner55484c42009-12-15 16:48:05 -0800952 if (!gru_assign_gru_context(gts)) {
Jack Steiner9a0deec2008-07-29 22:33:58 -0700953 preempt_enable();
Jack Steiner364b76d2009-06-17 16:28:20 -0700954 mutex_unlock(&gts->ts_ctxlock);
955 set_current_state(TASK_INTERRUPTIBLE);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700956 schedule_timeout(GRU_ASSIGN_DELAY); /* true hack ZZZ */
957 if (gts->ts_steal_jiffies + GRU_STEAL_DELAY < jiffies)
Jack Steiner55484c42009-12-15 16:48:05 -0800958 gru_steal_context(gts);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700959 goto again;
960 }
961 gru_load_context(gts);
962 paddr = gseg_physical_address(gts->ts_gru, gts->ts_ctxnum);
963 remap_pfn_range(vma, vaddr & ~(GRU_GSEG_PAGESIZE - 1),
964 paddr >> PAGE_SHIFT, GRU_GSEG_PAGESIZE,
965 vma->vm_page_prot);
966 }
967
Jack Steiner9a0deec2008-07-29 22:33:58 -0700968 preempt_enable();
Jack Steiner364b76d2009-06-17 16:28:20 -0700969 mutex_unlock(&gts->ts_ctxlock);
Jack Steiner9a0deec2008-07-29 22:33:58 -0700970
971 return VM_FAULT_NOPAGE;
972}
973